1. Field of the Invention
The present invention relates to an image location identification apparatus for matching image data taken by an ITV with a corresponding map stored as data in a database.
2. Description of the Background
In the case of monitoring an urban area by using an ITV (imaging television camera) loaded in a helicopter, it is necessary for captured image data to be matched with a corresponding map, which may represent administrative district data or road data, on a display.
For example, when a fire breaks out, a fire spot is taken by an ITV from the sky. Then the image data and its global location data (latitude, longitude and angle direction of view) are sent to a host computer. At the host computer, a map corresponding to the image data is retrieved from a map data base, according to the global location data. And the image data is matched with the map, which includes houses, buildings and road data, on display. Therefore, according to the outbreak point of a fire, the path of a fire after a prescribed time is simulated on the map. Then, against the path simulation, lead way and refuge places for inhabitants are determined.
In such a case, because the image data is matched with the map by using only the global location data, an error of several hundred meters may take place between the image data and the map, which are matched on the display. Therefore, if exact location identification is necessary for the image data and the map, the user must designate control points on the image data and the map for geometrical correction. However, because image data are sent momentarily, the designation of control points interactively is troublesome for user. Furthermore, if the user is not familiar with the neighborhood, he can not designate control points on the display rapidly.